The present invention relates to an articular pole assembly capable of winding.
My earlier U.S. Pat. No. 4,406,096 discloses an articular pole assembly capable of winding, comprising an articular pole and a take-up casing for storing the pole, the articular pole being composed of a continuous series of unit block members connected to one another by pins and by projection-notch engagements,with the proviso that, when the pole is pushed into the casing, the projection-notch engagements are released with disengaging means so as to make the pole rotatable about the pins, whereby the continuous series of unit block members can be stored in a wound or curved state in the casing. The unit block members each, disclosed in said U.S. Patent, has a pair of independent side plates and a connecting plate, the side plates of one unit block member being connected to the corresponding side plates of the adjacent unit block member by pins, the connecting plate having projections releasably engaged with notches of the side plates of the adjacent unit block member, with the proviso that the spring is employed to urge the projections of the connecting plate to push towards the notches of the side plates.
However, the known articular pole assembly mentioned above has somewhat insufficient strength, and therefore it is rather unsuitable for some industrial fields wherein a very strong and rigid pole structure having a high load suporting capacity are required. This is because the unit block members each of the known pole is composed of the three independent parts i.e. two side plates and one connecting plate. Furthermore, the fabrication of the known pole is difficult.